A general gas turbine is configured by a compressor, a combustor, and a turbine. Air taken in from an air inlet is compressed by a compressor, thereby becoming high-temperature and high-pressure compressed air. The combustor supplies fuel to the compressed air to burn the fuel, thereby acquiring high-temperature and high-pressure combustion gas (a working fluid). The turbine is driven by the combustion gas to drive a generator connected to the turbine.
In a conventional gas turbine combustor, a plurality of main combustion burners are arranged so as to surround a circumference of a pilot combustion burner, a pilot nozzle is incorporated in the pilot combustion burner, and a main nozzle is incorporated in the main combustion burners. The pilot combustion burner and the main combustion burners are arranged inside of an inner cylinder of the gas turbine.
As such a gas turbine combustor, there are gas turbine combustors described in Patent Literatures 1 and 2. A gas turbine combustor described in Patent Literature 1 has a configuration such that a sleeve is arranged outside of a body that forms a fuel passage, a cover ring is arranged therebetween to form an air passage inside and outside thereof, and a nozzle chip having a fuel injection hole that communicates with the fuel passage is provided at an apical end of the cover ring to configure a pilot nozzle. A gas turbine combustor described in Patent Literature 2 has a configuration such that a diffusion chip, which is a passage through which fuel, air, or an air-fuel mixture passes to function together with main and auxiliary mixing circuits, is provided in a fuel nozzle.